76-09-5

87199-18-6

214360-76-6

The general procedure for the synthesis of 3-hydroxyphenylboronic acid pinacol ester from pinacol and 3-hydroxyphenylboronic acid was as follows: 3-hydroxyphenylboronic acid (10.0 g, 72.46 mmol, 1.0 eq.) and dichloromethane (300 mL) were added to a 500 mL three-necked flask with pinacol (10.0 g, 84.60 mmol, 1.2 eq.) under stirring. Subsequently, the reaction mixture was stirred continuously for 48 hours at room temperature. Upon completion of the reaction, the reaction solution was poured into water (400 mL) and transferred to a partition funnel for separation. After separation of the organic phase, the aqueous phase was extracted twice with dichloromethane (400 mL). All organic phases were combined, dried with anhydrous sodium sulfate and filtered to remove the desiccant. The crude product was purified by column chromatography (using 200-300 mesh silica gel and a solvent mixture of dichloromethane/methanol as eluent, 100:1, v/v), resulting in 15.0 g of white solid product in 94% yield and 97% purity.